Nutr Res Pract.  2021 Aug;15(4):411-430. 10.4162/nrp.2021.15.4.411.

Dietary modulation of gut microbiota for the relief of irritable bowel syndrome

• Kim MY
• Choi SW

• KMID: 2518750
• DOI: http://doi.org/10.4162/nrp.2021.15.4.411

Abstract

Irritable bowel syndrome (IBS) is a frequently diagnosed gastrointestinal (GI) disorder characterized by recurrent abdominal pain, bloating, and changes in the stool form or frequency without any structural changes and overt inflammation. It is not a life-threatening condition but causes a considerable level of discomfort and distress. Among the many pathophysiologic factors, such as altered GI motility, visceral hypersensitivity, and lowgrade mucosal inflammation, as well as other immunologic, psychologic, and genetic factors, gut microbiota imbalance (dysbiosis), which is frequently found in IBS, has been highlighted as an etiology of IBS. Dysbiosis may affect gut mucosal homeostasis, immune function, metabolic regulation, and even visceral motor function. As diet is shown to play a fundamental role in the gut microbiota profile, this review discusses the influence of diet on IBS occurring through the modulation of gut microbiota. Based on previous studies, it appears that dietary modulation of the gut microbiota may be effective for the alleviation of IBS symptoms and, also an effective IBS management strategy based on the underlying mechanism; especially because, IBS currently has no specific treatment owing to its uncertain etiology.

Keyword

Irritable bowel syndrome; gut microbiota; dysbiosis; diet

Figure

• 

  Fig. 1 Interrelation between IBS and dysbiosis of the intestinal microbiota. Many extrinsic and intrinsic factors can influence the dysbiosis of intestinal microbiota, which has been suggested as a novel pathophysiologic mechanism of IBS. A hypothesis is proposed that dietary modulation may improve IBS symptoms by mitigating the dysbiosis.ENS, enteric nervous system; FODMAP, fermentable oligosaccharides, disaccharides, monosaccharides, and polyols; GI, gastrointestinal; IBS, irritable bowel syndrome.

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